In each study period at the end of the dry season and the end of the rainy season, for up to to three weeks in each study period, all patients > 6 months, presenting for clinical consultation at one of the 10 peripheral health centres participating in the study, responding to inclusion criteria and consenting to participate/with parental consent to participate, will be enrolled. All will be submitted free of charge to a thick film and a thin film for malaria, and a brief questionnaire on clinical history. All slides will be stored for further reading. Those patients with fever at presentation (axillary temperature >= 37.5°C), will be randomised (based on computer-generated random number lists) either to be submitted to a Paracheck® rapid test for malaria (cases), or to be managed the usual way, that is, on clinical grounds alone (controls). Only Paracheck® result will be used for decision on malaria treatment for cases. Treatment of controls, and treatment of any other condition for both cases and controls, will solely depend on the judgment of the clinical officer. No other formal algorithm will be followed than the national guidelines.